US4554523A - Winding for static induction apparatus - Google Patents

Winding for static induction apparatus Download PDF

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Publication number
US4554523A
US4554523A US06/658,026 US65802684A US4554523A US 4554523 A US4554523 A US 4554523A US 65802684 A US65802684 A US 65802684A US 4554523 A US4554523 A US 4554523A
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Prior art keywords
winding
coils
interleaved
terminal side
coil
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Expired - Fee Related
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US06/658,026
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English (en)
Inventor
Atsushi Miki
Etsunori Mori
Minoru Hoshi
Masaru Higaki
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Hitachi Ltd
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Hitachi Ltd
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F27/00—Details of transformers or inductances, in general
    • H01F27/34—Special means for preventing or reducing unwanted electric or magnetic effects, e.g. no-load losses, reactive currents, harmonics, oscillations, leakage fields
    • H01F27/343—Preventing or reducing surge voltages; oscillations

Definitions

  • the present invention relates to a high voltage winding for a static induction apparatus such as a transformer, a reactor and the like.
  • the invention is directed particularly to the winding for the static induction apparatus which exhibits a high series electrostatic capacitance effective for improving the surge withstanding characteristics and enhancing reliablility in respect of insulation.
  • an iron core type transformer a typical one of the static induction apparatus, comprises at least a low voltage winding and a high voltage winding wound around a leg portion of an iron core.
  • the high voltage winding is commonly constituted by a disk winding which comprises a plurality of disk-like or annular coils stacked axially and connected electrically in series, wherein each of the disk-like coils is formed by winding in a disk-like or radial spiral form a strand conductor usually insulated by an insulation sheet material such as kraft paper.
  • the disk winding for the transformer be capable of withstanding a steep wave front impulse voltage such as lightning surge which enters the transformer at a line terminal thereof.
  • the disk winding characteristically exhibits, when exposed to a steep wave front impulse voltage such as the surge voltage, a non-linear voltage distribution along all the length of the strand conductor from turn to turn, from coil to coil and from coil to the earth, as is well known in the art.
  • ⁇ the distribution constant
  • the interleaved winding has been based on such a principle that in order to provide the progressive or stepwise decreasing of the series electrostatic capacitance starting from the line terminal side (or high voltage end) toward other terminal such as a neutral point terminal, the interleaved coils may be wound in such a manner that potential differences between adjacent turns of the interlaced strand conductors are increased stepwise so as to increase the capacitance between the respective strand conductors, to thereby correspondingly increase the equivalent series capacitance. More specifically, the potential difference between the adjacent turns of the interlaced conductor which forms a coil is increased by varying the manner in which the strand conductor is interlaced or interleaved in winding the disk-like coils.
  • the interleaved winding is constituted by a plurality of annular or disk-like coils which are formed by winding a strand conductor or conductors coated with a suitable insulating material which are coaxially stacked in the axial direction of the winding and sequentially connected in a series circuit relation between the line terminal and the other terminal such as the neutral terminal, wherein the winding is divided into a predetermined number of sections or blocks, e.g. three blocks, each including a predetermined number of the disk-like coils.
  • the coils belonging to the different blocks are so formed as to exhibit different series capacitances. More particularly, those coils which belong to the first block disposed on the side of the line terminal (i.e.
  • the coils belonging to this block are also wound in the interleaved structure similar to the coils of the first block.
  • each of the coils belonging to the second block a plurality of second thin insulation spacers are disposed between the adjacent turns of the strand conductor in a dispersed manner, wherein the thickness of each second insulation spacer is so selected that the sum of the thicknesses of all the second insulation spacers is substantially equal to the thickness of the first insulation spacer mentioned above.
  • the coil belonging to the second block or group thus presents a lower series static capacitance because the capacitance between the adjacent turns is decreased by the provision of the second insulation spacers.
  • each coil is constituted by the conventional disk-like or annular coil realized by winding a single strand conductor in a non-interleaved manner and having a number of turns increased by a number of the insulation spacers spaced in this block.
  • the winding composed of a number of the coil blocks of different arrangements is imparted with the series static capacitance which is decreased progressively or stepwise from one to another block starting from the block located on the line terminal side toward the other terminal and thus exhibits improved surge voltage withstanding characteristics.
  • An object of the present invention is to provide an improved structure of a winding for a static induction apparatus such as a transformer, a reactor and the like in which potential distribution along the axis of the winding is made more uniform throughout from the line terminal side to the other terminal side and which exhibits improved surge or impulse voltage withstanding characteristics as well as an enhanced reliability of insulation and, besides, allows the volume of the winding to be reduced.
  • a winding for a static induction apparatus which comprises a plurality of interleaved coils connected sequentially in series to one another between a line terminal and another terminal such as neutral point terminal, the winding being divided into a predetermined number of blocks or groups each including a plurality of the interleaved coils, wherein the number of turns of the interleaved coil belonging to the block located on the other terminal side is decreased as compared with the number of turns of the interleaved coils belonging to the block disposed on the line terminal side.
  • FIG. 1 schematically illustrates a winding for a static induction apparatus according to an exemplary embodiment of the invention
  • FIGS. 2A and 2B show coils used in the winding shown in FIG. 1 in enlarged sectional views
  • FIGS. 3, 4 and 5 illustrate exemplary dispositions of windings in transformers to which the winding according to the invention is applied;
  • FIG. 6 illustrates graphically and comparatively an initial potential distribution brought about by lightning surges in a winding for the static induction apparatus according to the invention which has a line terminal provided at a center or mid point as viewed in the axial direction of the winding;
  • FIGS. 7A and 7B are enlarged sectional views showing, respectively, other examples of coils employed in the winding according to the invention.
  • FIG. 8 shows schematically a structure of the winding for a static induction apparatus according to a further embodiment of the invention.
  • FIG. 9 shows schematically a structure of the winding for a static induction apparatus according to still another embodiment of the invention.
  • the transformer winding as illustrated comprises a plurality of coils each of an interleaved structure in which a single or more strand conductors coated with a suitable insulation material is or are wound alternately radially inward and radially outward or vice versa.
  • These disk-like coils of the interleaved structure are stacked coaxially in the axial direction of the winding and electrically connected sequentially in series between a line terminal U and another terminal O such as a neutral point terminal.
  • the transformer winding is divided into, for example, three blocks or groups designated by I, II and III between the line terminal U and the other terminal O such as the neutral point terminal or a line terminal of an intermediate voltage.
  • the coil blocks I, II and III include a plurality of coils C I , a plurality of coils C II and a plurality of coils C III , respectively, of the interleave structure which are stacked axially and are electrically connected sequentially in a series circuit relation.
  • the interleaved coils C I , C II and C III of the respective blocks I, II and III are of the identical interleave structure with the two outermost turns of the coils being connected in an interlaced fashion.
  • the number of turns of the interleaved coil differs from one to another block. More specifically, when the number of turns of the coils belonging to the blocks I, II and III are represented by N I , N II , N III , then the numbers of turns of the coils in these blocks are so selected that N I >N II >N III . In other words, the number of turns of the coils is decreased stepwise from the block I to II and hence to III so that the relation: N I >N II >N III applies valid.
  • the size or dimension of the interlaced strand conductors 10A, 10B and 10C of the coils C I , C II and C III are correspondingly varied in the case of the illustrated embodiment, although adjusting pieces or spacers of an insulation material may be used for the same purpose.
  • the dimension H I of the strand conductor 10A in the radial direction of the coil is selected smaller as compared with the corresponding dimensions of the strand conductors 10B and 10C of the coils C II and C III belonging to the other blocks II and III, while the dimension W I of the strand conductor 10A in the axial direction of the stacked coils is selected larger as compared with the corresponding ones of the other strands 10B and 10C, whereby the number of turns N I of the coil C I is increased, as is illustrated in FIG. 2A.
  • the strand conductor 10A is coated with a suitable insulation material 11A such as kraft paper.
  • the strand conductor 10C which constitutes the interleaved coil C III belonging to the block III disposed closest to the other terminal O has a greater dimension H III in the radial direction of the coil and a smaller dimension W III in the axial direction of the stacked coils, whereby the number bf turns N III of the coil C III is decreased, as can be seen from FIG. 2B.
  • the strand conductor 10C is also coated with the insulation material 11C.
  • the strand conductor forming the coil C II belonging to the block II is imparted with intermediate dimensions both in the radial and axial directions and coated with an insulation material, although not shown in the drawing whereby the number of turns N II of the coil C II is correspondingly determined.
  • the series static capacitance of the interleaved coil is in proportion to the number of turns (N) of the disk-like coil and the dimension W of the strand conductor in the axial direction and in reciprocal proportion to the thickness t of the insulation provided between adjacent strand conductors. Accordingly, the coils of the block disposed on the line terminal side can be increased in respect of the series static capacitance by increasing the number of turns N I and the dimension in the axial direction of the winding, and additionally the freedom in reducing gradually the distribution of the series capacitance can be enhanced significantly.
  • the transformer winding of the structure described above, according to the present invention can be formed of a single continuous strand conductor extending continuously from the top end to the bottom end of the winding in a manner illustrated in FIG. 1 and wound around a leg portion of the iron core TC as a high voltage winding H together with a low voltage winding L, and if desired, a tertiary winding T in a coaxial manner, as is illustrated in FIG. 3.
  • the transformer winding according to the invention can be used in a connection shown in FIG. 4 in which a center point of the winding serves as the line terminal U while the upper and the lower ends of the winding are connected together in parallel connection to serve as the other terminal O in a multi-winding type transformer.
  • FIGS. 4 In FIGS.
  • the winding according to the invention is made use of as a high voltage series winding H in an autotransformer with a center tap thereof being used as the line terminal U, while the upper and the lower ends u of the winding H are combined together in a parallel connection which is then connected in series with a shunt winding L which may be constituted by conventional non-interleaved disk-like coils or constituted at least partially by the interleaved coils and wound around the leg portion TC of the iron core together with a tertiary winding T.
  • a shunt winding L which may be constituted by conventional non-interleaved disk-like coils or constituted at least partially by the interleaved coils and wound around the leg portion TC of the iron core together with a tertiary winding T.
  • other connections of the windings may be adopted, as occasion requires.
  • FIG. 6 graphically illustrates the initial potential distribution along the axial direction of the winding as brought about in response to impression of a lightning surge where the windings according to the invention are stacked one on another and connected in a parallel relation.
  • the curve 20A representing the potential distribution in the winding according to the invention approximates more an ideal uniform potential distribution curve depicted by a single-dotted broken line as compared with a potential distribution curve 20B for an interleaved winding of a hitherto known structure and is more linearized. It will thus be understood that the impulse voltage characteristics can further be improved, resulting in an enhanced reliability and stability of insulation.
  • the reduced axial dimension of the strand conductors constituting the interleaved coils disposed at these regions is also effective for reducing the eddy current loss.
  • FIGS. 7A and 7B show structures of the interleaved coils C I and C III belonging to the coil blocks I and III, respectively, according to another embodiment of the invention.
  • the structures of the interleaved coils illustrated in these figures assure the appropriate distribution of the series static capacitance throughout the winding constituted by these coils C I , C II (not shown), C III and improved insulation characteristics.
  • the cross-sectional configuration and dimensions or size of the strand conductors constituting the interleaved coils are same throughout all the blocks I, II and III.
  • the thickness of the insulation coat such as kraft paper applied to the strand conductor is varied in dependence on the blocks to which the respective interleaved coils belong. More particularly, in the case of the interleaved coil C I belonging to the coil block I located closest to the line terminal U shown in FIG. 1, the strand conductor 30A is applied with the insulation coat 31A having a thickness of t I and wound to form the coil C I . On the other hand, in the case of the interleaved coil C III belonging to the coil block III disposed closest to the other terminal, the strand conductor 30C is applied with the insulation coat 31C having a greater thickness t III than that of the insulation coat 31A for the conductor 30A.
  • the thickness of the insulation coat applied to the strand conductor forming the interleaved coil C II which belongs to the coil block II located between the blocks I and III is selected to lie between the thickness t I and t III , although the insulated strand conductor for the coil C II is not shown in these figures.
  • the number of turns of each interleaved coil C I , C II , C III can be selected such that the relation: N I >N II >N III described hereinbefore is established.
  • the interleaved coils C 1 , C II and C III formed of the respective strand conductors enclosed by the insulation coats having different thicknesses allow the winding to be manufactured with the radial dimensions D I , D II and D III of the coils C I , C II and C III being maintained substantially same without resorting to the use of the insulation spacer or the like.
  • the series electrostatic capacitance of the disk-like interleaved coil is in proportion to the number of turns N of the coil and to the dimension W of the strand conductor in the axial direction of the coil, but is in reciprocal proportion to the thickness T of the insulation layer located between the adjacent turns of the strand conductor. Accordingly, it is possible to attain a great series capacitance in a gradient distribution in the winding by increasing the number of turns N of the interleaved coil and reducing the thickness of the insulation coat in the cqil block located closest to the line terminal. Further, the radial dimensions of the interleaved coils belonging to the different blocks can be made substantially uniform without resorting to the use of other means.
  • FIGS. 7A and 7B provides the advantages similar to those of the coil described hereinbefore in conjunction with FIGS. 2A and 2B.
  • FIG. 8 shows a winding according to another embodiment of the invention.
  • This winding is also divided into three blocks I, II and III including, respectively, a plurality of interleaved coils C I , C II and C III in series circuit relation between the line terminal U and the other terminal O, similarly to the case of FIG. 1.
  • each of the interleaved coils C I is wound as formed of an insulated strand conductor 10A having a diminished radial dimension and an increased axial dimension such as the one shown in FIG.
  • each of the interleaved coils C III is formed of an insulated strand conductor 10C having a greater radial dimension and a reduced axial dimension such as the one shown in FIG. 2B to thereby reduce the number of turns.
  • the intermediate block II there are provided a pair of interleaved coils C II each of which is formed by winding the strand conductors 10A and 10C described above in the interleaved manner for a predetermined number of turns.
  • the strand conductor 10C is led out from the last turn 116 of the interleaved coil C II without being cut and wound together with the identical counterpart conductor 10C to thereby form the interleaved coil C III belonging to the block III, whereby the otherwise required electrical connection at a mid point Q 2 can be spared, since no electrical discontinuation is present between the coils II and III with respect to the conductor 10C.
  • the coil block II including a pair of interleaved coils formed of the paired strand conductors 10A and 10C of the coils C I and C III , respectively, between the blocks I and III, the electrical connections between the adjacent coil blocks become unnecessary, whereby the winding operation can be effected in a continuous manner.
  • the interleaved winding of the structure illustrated in FIG. 8 provides the advantages described hereinbefore and allows the series static capacitance of large capacity to be established with an increased freedom in distributing the electrostatic capacitance in a progressively decreased distribution from the high voltage end toward a low voltage end of the winding. Besides, electrical connection is rendered unnecessary, reliable insulation is attained and the manufacturing of the winding in much facilitated, to the additional advantages.
  • FIG. 9 shows a winding according to still another embodiment of the invention which differs from the structure of the winding shown in FIG. 1 in that a fourth coil block IV is provided closest to the other terminal O in addition to the blocks I, II and III including, respectively, the interleaved coils C I , C II and C III in the arrangement similar to those shown in FIG. 1.
  • the block IV includes a plurality of conventional (non-interleaved) coils each formed of the same strand conductor as the conductor 10C and exhibiting more reduced series capacitance.
  • the number of blocks constituting the winding may be selected rather arbitrarily.
  • any of the interleaved coils is formed of a single conductor.
  • paralleled strand conductors or transposed conductor including a number of fine strands and encased in an insulation sheath may be employed when the current capacity of the winding to be manufactured has to be increased.
  • various interleaved structures known in the art may be made use of.
  • the potential distribution in the axial direction of the winding can be much linearized with the decreased distribution constant ⁇ by virtue of the arrangement that the series static capacitance of the coils belonging to the different blocks can be decreased stepwise as the conductor proceeds from the line terminal side toward the other terminal side, whereby improved surge voltage characteristic as well as reliable insulation of the winding can be accomplished. Further, since no special insulation spacers are used, the space factor of the winding is increased so that the volume of the winding can be reduced significantly.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Coils Of Transformers For General Uses (AREA)
US06/658,026 1980-03-05 1984-10-05 Winding for static induction apparatus Expired - Fee Related US4554523A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP55-26666 1980-03-05
JP55026666A JPS609650B2 (ja) 1980-03-05 1980-03-05 高直列容量変圧器巻線

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US (2) US4554523A (OSRAM)
JP (1) JPS609650B2 (OSRAM)
CA (1) CA1153433A (OSRAM)
DE (1) DE3108161C2 (OSRAM)
GB (1) GB2071921B (OSRAM)
IN (1) IN153215B (OSRAM)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4859978A (en) * 1988-04-29 1989-08-22 Electric Power Research Institute, Inc. High-voltage windings for shell-form power transformers
US4864266A (en) * 1988-04-29 1989-09-05 Electric Power Research Institute, Inc. High-voltage winding for core-form power transformers
US5508674A (en) * 1992-03-25 1996-04-16 Electric Power Research Institute, Inc. Core-form transformer
US20140218151A1 (en) * 2011-08-30 2014-08-07 Abb Technology Ag Dry-Type Transformer
US20140327509A1 (en) * 2011-12-20 2014-11-06 Alstom Technology Ltd. High impedance air core reactor

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3268234D1 (en) * 1982-04-21 1986-02-13 Esslinger Spezielektra Reactor, particularly air isolated reactor without magnetic core
US5160820A (en) * 1990-03-30 1992-11-03 Honda Giken Kogyo Kabushiki Kaisha Welding transformer and method of manufacturing same
JP7016683B2 (ja) * 2017-12-07 2022-02-07 株式会社日立製作所 静止誘導電器

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US2905911A (en) * 1954-06-08 1959-09-22 Hitachi Ltd Static shielding of transformer windings
US3106690A (en) * 1958-12-10 1963-10-08 Wagner Electric Corp Electrical induction apparatus
FR1526293A (fr) * 1967-04-14 1968-05-24 Jeumont Schneider Perfectionnements aux bobinages de réactances sans noyau de fer, à haute tension
US3387243A (en) * 1966-03-30 1968-06-04 Gen Electric Inductive disk winding with improved impulse voltage gradient
US3392326A (en) * 1966-09-28 1968-07-09 Gen Electric Coil winding buffer conductors having impedance means
US3528046A (en) * 1966-11-22 1970-09-08 Gen Electric Interlaced disk winding with improved impulse voltage gradient
US3560902A (en) * 1967-06-14 1971-02-02 Hitachi Ltd Method of providing static shielding of transformer windings
US3564470A (en) * 1969-04-16 1971-02-16 Westinghouse Electric Corp Electrical winding structures
US3705371A (en) * 1972-02-22 1972-12-05 Westinghouse Electric Corp Electrical winding
US3781739A (en) * 1973-03-28 1973-12-25 Westinghouse Electric Corp Interleaved winding for electrical inductive apparatus
JPS5192025A (OSRAM) * 1975-02-10 1976-08-12
JPS5521168A (en) * 1978-08-02 1980-02-15 Meidensha Electric Mfg Co Ltd Circular winding for stationary induction electric machine

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GB1001512A (en) 1960-11-24 1965-08-18 English Electric Co Ltd Improvements in or relating to electric transformers
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GB988657A (en) * 1962-12-26 1965-04-07 Mizuno Akira An internal combustion engine throttle control device
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JPH0710204B2 (ja) * 1992-06-30 1995-02-08 井関農機株式会社 全稈投入型コンバインの刈取ロ−リング装置

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1641658A (en) * 1927-09-06 Paper-break detector switch
US2879354A (en) * 1954-05-26 1959-03-24 Westinghouse Electric Corp Fusible devices
US2905911A (en) * 1954-06-08 1959-09-22 Hitachi Ltd Static shielding of transformer windings
US3106690A (en) * 1958-12-10 1963-10-08 Wagner Electric Corp Electrical induction apparatus
US3387243A (en) * 1966-03-30 1968-06-04 Gen Electric Inductive disk winding with improved impulse voltage gradient
US3392326A (en) * 1966-09-28 1968-07-09 Gen Electric Coil winding buffer conductors having impedance means
US3528046A (en) * 1966-11-22 1970-09-08 Gen Electric Interlaced disk winding with improved impulse voltage gradient
FR1526293A (fr) * 1967-04-14 1968-05-24 Jeumont Schneider Perfectionnements aux bobinages de réactances sans noyau de fer, à haute tension
US3560902A (en) * 1967-06-14 1971-02-02 Hitachi Ltd Method of providing static shielding of transformer windings
US3564470A (en) * 1969-04-16 1971-02-16 Westinghouse Electric Corp Electrical winding structures
US3705371A (en) * 1972-02-22 1972-12-05 Westinghouse Electric Corp Electrical winding
US3781739A (en) * 1973-03-28 1973-12-25 Westinghouse Electric Corp Interleaved winding for electrical inductive apparatus
JPS5192025A (OSRAM) * 1975-02-10 1976-08-12
JPS5521168A (en) * 1978-08-02 1980-02-15 Meidensha Electric Mfg Co Ltd Circular winding for stationary induction electric machine

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4859978A (en) * 1988-04-29 1989-08-22 Electric Power Research Institute, Inc. High-voltage windings for shell-form power transformers
US4864266A (en) * 1988-04-29 1989-09-05 Electric Power Research Institute, Inc. High-voltage winding for core-form power transformers
US5508674A (en) * 1992-03-25 1996-04-16 Electric Power Research Institute, Inc. Core-form transformer
US20140218151A1 (en) * 2011-08-30 2014-08-07 Abb Technology Ag Dry-Type Transformer
US9147520B2 (en) * 2011-08-30 2015-09-29 Abb Technology Ag Dry-type transformer
US20140327509A1 (en) * 2011-12-20 2014-11-06 Alstom Technology Ltd. High impedance air core reactor
US9633777B2 (en) * 2011-12-20 2017-04-25 Alstom Technology Ltd. High impedance air core reactor

Also Published As

Publication number Publication date
DE3108161A1 (de) 1982-01-21
IN153215B (OSRAM) 1984-06-16
US4571570A (en) 1986-02-18
JPS609650B2 (ja) 1985-03-12
CA1153433A (en) 1983-09-06
GB2071921B (en) 1983-10-19
DE3108161C2 (de) 1983-12-29
JPS56124219A (en) 1981-09-29
GB2071921A (en) 1981-09-23

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